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Diffstat (limited to 'drivers/interconnect/samsung/exynos.c')
-rw-r--r--drivers/interconnect/samsung/exynos.c199
1 files changed, 199 insertions, 0 deletions
diff --git a/drivers/interconnect/samsung/exynos.c b/drivers/interconnect/samsung/exynos.c
new file mode 100644
index 000000000..72e426038
--- /dev/null
+++ b/drivers/interconnect/samsung/exynos.c
@@ -0,0 +1,199 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Exynos generic interconnect provider driver
+ *
+ * Copyright (c) 2020 Samsung Electronics Co., Ltd.
+ *
+ * Authors: Artur Świgoń <a.swigon@samsung.com>
+ * Sylwester Nawrocki <s.nawrocki@samsung.com>
+ */
+#include <linux/device.h>
+#include <linux/interconnect-provider.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/pm_qos.h>
+#include <linux/slab.h>
+
+#define EXYNOS_ICC_DEFAULT_BUS_CLK_RATIO 8
+
+struct exynos_icc_priv {
+ struct device *dev;
+
+ /* One interconnect node per provider */
+ struct icc_provider provider;
+ struct icc_node *node;
+
+ struct dev_pm_qos_request qos_req;
+ u32 bus_clk_ratio;
+};
+
+static struct icc_node *exynos_icc_get_parent(struct device_node *np)
+{
+ struct of_phandle_args args;
+ struct icc_node_data *icc_node_data;
+ struct icc_node *icc_node;
+ int num, ret;
+
+ num = of_count_phandle_with_args(np, "interconnects",
+ "#interconnect-cells");
+ if (num < 1)
+ return NULL; /* parent nodes are optional */
+
+ /* Get the interconnect target node */
+ ret = of_parse_phandle_with_args(np, "interconnects",
+ "#interconnect-cells", 0, &args);
+ if (ret < 0)
+ return ERR_PTR(ret);
+
+ icc_node_data = of_icc_get_from_provider(&args);
+ of_node_put(args.np);
+
+ if (IS_ERR(icc_node_data))
+ return ERR_CAST(icc_node_data);
+
+ icc_node = icc_node_data->node;
+ kfree(icc_node_data);
+
+ return icc_node;
+}
+
+static int exynos_generic_icc_set(struct icc_node *src, struct icc_node *dst)
+{
+ struct exynos_icc_priv *src_priv = src->data, *dst_priv = dst->data;
+ s32 src_freq = max(src->avg_bw, src->peak_bw) / src_priv->bus_clk_ratio;
+ s32 dst_freq = max(dst->avg_bw, dst->peak_bw) / dst_priv->bus_clk_ratio;
+ int ret;
+
+ ret = dev_pm_qos_update_request(&src_priv->qos_req, src_freq);
+ if (ret < 0) {
+ dev_err(src_priv->dev, "failed to update PM QoS of %s (src)\n",
+ src->name);
+ return ret;
+ }
+
+ ret = dev_pm_qos_update_request(&dst_priv->qos_req, dst_freq);
+ if (ret < 0) {
+ dev_err(dst_priv->dev, "failed to update PM QoS of %s (dst)\n",
+ dst->name);
+ return ret;
+ }
+
+ return 0;
+}
+
+static struct icc_node *exynos_generic_icc_xlate(struct of_phandle_args *spec,
+ void *data)
+{
+ struct exynos_icc_priv *priv = data;
+
+ if (spec->np != priv->dev->parent->of_node)
+ return ERR_PTR(-EINVAL);
+
+ return priv->node;
+}
+
+static int exynos_generic_icc_remove(struct platform_device *pdev)
+{
+ struct exynos_icc_priv *priv = platform_get_drvdata(pdev);
+ struct icc_node *parent_node, *node = priv->node;
+
+ icc_provider_deregister(&priv->provider);
+
+ parent_node = exynos_icc_get_parent(priv->dev->parent->of_node);
+ if (parent_node && !IS_ERR(parent_node))
+ icc_link_destroy(node, parent_node);
+
+ icc_nodes_remove(&priv->provider);
+
+ return 0;
+}
+
+static int exynos_generic_icc_probe(struct platform_device *pdev)
+{
+ struct device *bus_dev = pdev->dev.parent;
+ struct exynos_icc_priv *priv;
+ struct icc_provider *provider;
+ struct icc_node *icc_node, *icc_parent_node;
+ int ret;
+
+ priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ priv->dev = &pdev->dev;
+ platform_set_drvdata(pdev, priv);
+
+ provider = &priv->provider;
+
+ provider->set = exynos_generic_icc_set;
+ provider->aggregate = icc_std_aggregate;
+ provider->xlate = exynos_generic_icc_xlate;
+ provider->dev = bus_dev;
+ provider->inter_set = true;
+ provider->data = priv;
+
+ icc_provider_init(provider);
+
+ icc_node = icc_node_create(pdev->id);
+ if (IS_ERR(icc_node))
+ return PTR_ERR(icc_node);
+
+ priv->node = icc_node;
+ icc_node->name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "%pOFn",
+ bus_dev->of_node);
+ if (of_property_read_u32(bus_dev->of_node, "samsung,data-clock-ratio",
+ &priv->bus_clk_ratio))
+ priv->bus_clk_ratio = EXYNOS_ICC_DEFAULT_BUS_CLK_RATIO;
+
+ icc_node->data = priv;
+ icc_node_add(icc_node, provider);
+
+ /*
+ * Register a PM QoS request for the parent (devfreq) device.
+ */
+ ret = dev_pm_qos_add_request(bus_dev, &priv->qos_req,
+ DEV_PM_QOS_MIN_FREQUENCY, 0);
+ if (ret < 0)
+ goto err_node_del;
+
+ icc_parent_node = exynos_icc_get_parent(bus_dev->of_node);
+ if (IS_ERR(icc_parent_node)) {
+ ret = PTR_ERR(icc_parent_node);
+ goto err_pmqos_del;
+ }
+ if (icc_parent_node) {
+ ret = icc_link_create(icc_node, icc_parent_node->id);
+ if (ret < 0)
+ goto err_pmqos_del;
+ }
+
+ ret = icc_provider_register(provider);
+ if (ret < 0)
+ goto err_pmqos_del;
+
+ return 0;
+
+err_pmqos_del:
+ dev_pm_qos_remove_request(&priv->qos_req);
+err_node_del:
+ icc_nodes_remove(provider);
+
+ return ret;
+}
+
+static struct platform_driver exynos_generic_icc_driver = {
+ .driver = {
+ .name = "exynos-generic-icc",
+ .sync_state = icc_sync_state,
+ },
+ .probe = exynos_generic_icc_probe,
+ .remove = exynos_generic_icc_remove,
+};
+module_platform_driver(exynos_generic_icc_driver);
+
+MODULE_DESCRIPTION("Exynos generic interconnect driver");
+MODULE_AUTHOR("Artur Świgoń <a.swigon@samsung.com>");
+MODULE_AUTHOR("Sylwester Nawrocki <s.nawrocki@samsung.com>");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:exynos-generic-icc");